We additionally compute the Dice loss [1]} between rasterized polygons as auxiliary loss:
\(\mathcal {L}_{\text{ras}}^{m} = {1}_{\left\lbrace  m\le M^\text{gt} \right\rbrace } \text{Dice}\big (R(P_{m}), R(\hat{P}_{\hat{\sigma }(m)})\big )\) 
